seating depth comparator inserts- Warning

[dogfox1]

Inserts for seating depth comparator tools like the stoney point one.

 

 

Something that was brought home to me when doing some checks on some bullets which is not really important, but fact is that all inserts are not created equal.

 

I have used them for years and it was only when I used another insert for checking some bullets were ok I found there was major differences in readings between the two of the same calibre.

 

 

If one checked the seating depth to the lands using one insert and checked loaded rounds with another insert you be in real trouble, I found they are far being inter changeable. They are only comparators

 

Check loaded rounds with the same insert that you measured the seating depth with or you be in the pooo.

 

Sorry if common sense but its for the newboys to reloading really, not wishing to tell people to suck eggs.

[6mmBR]

Thanks for the heads up.

Dave

[Ratwhiskers]

Good shout up there fella

 

People should remember not the chop and change variables half way through a procedure, or very often the words....... WHOOOPS!!!!!!! can be heard when least needed.

[Davy]

That is worrying.

 

The comparator and red anodised holder should measure exactly 1.000" long fitted in the vernier. (I make my own comparator inserts which are slightly longer at 1.100") I only have one of each insert so I have never seen a problem, however I have more than one comparator block so I will have a measure and see if there is any difference. How much of a variance do you see?

[1967spud]

as long as you zero your caipers before measuring you shuold beok

[brown dog]

Presumably the difference being reported here (great heads-up by the way ) lies with the characteristics of the comparator hole and where slightly different comparator holes allow the insert to sit on the ogive.

[1967spud]

exactly true BD you shuold never mix match measuring operations or measuring devices during or even from time to time as differances will occur

 

 

 

it doesn t matter if your tape measure doesnt measure the same as the next but as long as you use the same one all the time the measurements will be comparable with each other

 

 

simples!

[garyw]

as long as you zero your caipers before measuring you shuold beok

spud -have you been on the silly bugger juice?

[1967spud]

lol typo fwt

[dogfox1]

Hi Spud,

 

That's just it using the same insert all the time.

 

Zeroing the verniers in this would make no difference because as Brown Dog said its where on the ogive that the insert contacts the bullet. The size of the hole.

 

In this case the bullet goes visibly further into the insert than the other one.

[andybrock]

I suppose anything that is semi or mass produced like Stoney point measuring tools will have a degree of tolerance discrepancy, I would imagine any measurement critical tool would be regularly calibrated.

[tony]

Good heads up there........Although I only have one for each caliber, cant afford two,

Tony.

[dogfox1]

I only purchased a second one so I could measure bearing surface in one go, rather than in three goes.

[Vermincinerator]

like dogfox said these devices are for comparing one cartridge to another and are not strictly a measuring device.

I use a dummy round for which ever cartridge/bullet combo i am loading to get a datum measurement for the seating depth i need.

 

Ian.